A question or two about aircraft simulators, post-1960

[greenmartian2017]

I thought I would put the following questions to the assembled, in the hopes someone might know more.

a)--If McDonnell Douglas had aircraft simulators in the late 1960s, where would these have been located? (Are there pictures?)

and

b)--In the sequence of development of an aircraft, how far along in the plane's development do aircraft simulators (the ones that pilots sit in to learn how to fly the creature) appear?

If anyone can talk to these two questions, please hold forth.

Thanks very much.

 

[DWG]

Simulators have been around since WWI, so it's extremely unlikely McDAC didn't have them by the 60s.

Simulators are usually being used well before the design is finalised, and similarly well before hardware remotely resembles an aircraft. For instance on 777 Boeing was using simulators to develop the flight control laws well in advance of us writing the actual flight control code that would fly, while on Eurofighter ISTR there was considerable tactical development going on before we were regularly flying the aircraft.

It's important to understand that at this stage simulators aren't being used to 'learn to fly the aircraft', they're an integral part of the engineering development programme. Mostly that'll be done by test pilots, but a friend seconded to Seattle was occasionally asked to fly the 777 development sim around for an hour or two, even though he's never flown anything larger than a Robin, so that the Boeing engineers could monitor how the iron bird rig it was linked to was reacting with the code he'd just delivered.

Engineering Simulation typically starts with someone doodling on the back of an envelope well in advance of formal launch. Then there'll be a lot of Operational Research style analysis/simulation (even for the civilian projects) to optimise the requirements, before ever getting into the engineering development.

Using the simulator solely to learn to fly the aircraft ab initio doesn't really happen until quite late in the programme, when you're looking at new pilots coming onboard for service acceptance trials etc, before that people will be learning organically in parallel with engineering development.

 

[greenmartian2017]

Thanks DWG. I appreciate the comments. These help further things some.

Let me provide more context. After you read this DWG, could you please comment some more as to where the stage might be as to what is being talked about here? From an interview with Paul Czysz, as conducted by Tim Ventura, a long while back (prior to 2013). This is about one of the McDonnell Douglas hypersonic programs.
URL link to the main section: https://medium.com/@timventura/paul-czysz-on-hypersonic-aircraft-suborbital-spaceplanes-92ed10537ee6.


"...

Now you’ve talked about losing test-pilots during this process also, right? I remember you saying something about the aerodynamics being very counterintuitive at hypersonic speeds…

No, no — we didn’t actually lose test-pilots — I was referring to the aerodynamics during training in a hypersonic flight simulator. The bottom of the aircraft in a Mach 8 to 12 scramjet is the engine. Now the way you get an engine to put out more thrust is to increase the capture area of the engine — that’s how you get the variable capture inlet area on the F-15 — you can control the thrust level potential by controlling the airflow to the engine.

So if you have a scramjet vehicle, and you want to increase the thrust of it, you have to increase its angle of attack — not by much, only by about 2 or 3 degrees. Nevertheless, as you advance the throttle, the nose comes up, and that’s very counterintuitive to a pilot, who will think that the nose coming up when you advance the throttle means that there’s something wrong.

So in the simulator, these pilots were not pulling up, but they were advancing the throttle. Again, in order to get more thrust out of a ram-compression engine you have to increase the capture area, and the way that you increase the capture area is to pull the nose up — and since the whole bottom of the aircraft is the engine, it increases its capture area.
..."

Based on this meager amount of information DWG, where do you think the simulators that are mentioned were coming in at in the vehicle's development?

 

[gtg947h]

I used to design the mechanical side of the kinds of simulators you’re talking about. Most likely, what they’re using is a generic simulator, probably PC-based albeit running custom software. I’d expect a mockup, generic cockpit with some generic flight control hardware (either high-end commercial units, or older/spare units taken from a FBW military aircraft).

I’d bet they were being used fairly early in the dev cycle—as soon as you had a preliminary concept and could generate some performance characteristics, you could start mocking up a simulated vehicle to test it. I know on the programs I worked (transport-category civil aircraft) we were using custom-written sim software for the aircraft behavior side, a commercial PC sim for the out-the-window display (our custom sim just fed it a position), and supplier prototype/eval flight control units for the pilot controls. We used it very early on to try out some cockpit interaction ideas, flight control laws, etc.

This was probably two years before we started building the iron bird and avionics test rigs (which also ran hooked up to simulations, but with the aircraft side being real hardware—avionics, flight control electronics, etc). Our test pilots spent a lot of time in them but it wasn’t really “learning to fly” the airplane, more practicing procedures and rehearsing tests. The moving-base pilot training sims didn’t really come online until after the flight test program was well underway.

We also had an avanced-concept really early prototype sim that was all PC-based commercial sims and hardware running in a wooden mockup; we used that for a few theories we had on synthetic vision and other advanced avionics concepts.

 

[greenmartian2017]

Thanks GTG.

Do you think that what you describe has been a long-term S.O.P. for flight simulators (how they are designed, and when they appear in the development cycle)? I am suspecting that this hypersonic vehicle simulator was extant in the mid- or late 1960s, or possibly in the early 1970s.

I also wonder whether there are any McDonnell Douglas histories that might talk more about this subject. Problem is, I am not clued in as to whether this may exist or not.

It's too bad that Dr. Czysz isn't alive, or I would ask him directly myself.

 

[gtg947h]

My experience was in the mid 2000s up to 2014 or so, so anything I’d throw out for the 60s and 70s would be almost pure speculation. But, I’m pretty sure I remember reading about/seeing simulators for the F-108, X-20, etc. and those never flew; I think there were X-15 sims as well. How they were built, or exactly what phase of development they came in, I don’t know.

 

[Hood]

From a British perspective a lot of work was done on simulators from the 1950s onwards. Miles Engineering seem to have been a big supplier during the 1960s.
TSR.2 had test rigs and I know some work was done on simulators for training but were cancelled but elements were re-used on the Phantom simulators.

 

[DWG]

"...

...I was referring to the aerodynamics during training in a hypersonic flight simulator.

Based on this meager amount of information DWG, where do you think the simulators that are mentioned were coming in at in the vehicle's development?

As no one has flown a manned scramjet (that we know of), this is by definition engineering development.

 

[DWG]

I used to design the mechanical side of the kinds of simulators you’re talking about. Most likely, what they’re using is a generic simulator, probably PC-based albeit running custom software.

Not in the 1960s, or even the mid-80s.

 

[DWG]

From a British perspective a lot of work was done on simulators from the 1950s onwards. Miles Engineering seem to have been a big supplier during the 1960s.
TSR.2 had test rigs and I know some work was done on simulators for training but were cancelled but elements were re-used on the Phantom simulators.

I know a late friend did engineering development simulation work on Rapier using an analogue computer that now resides at the Science Museum. While he was never precise on when that was, I'd guess mid-60s (the wiki article on Rapier also talks about simulation work in 1965, and is a good example of the kind of development issue it's applicable to, but that's probably not the same work he was engaged in as that was Rochester-based, not Woomera).

 

[gtg947h]

I used to design the mechanical side of the kinds of simulators you’re talking about. Most likely, what they’re using is a generic simulator, probably PC-based albeit running custom software.

Not in the 1960s, or even the mid-80s.

True; I was thinking of current engineering development sims (e.g. the 777 and Typhoon programs you mentioned, the civil programs I worked on, etc), not the hypersonic ones mentioned here.

 

[RetiredAFGuy]

I used to design the mechanical side of the kinds of simulators you’re talking about. Most likely, what they’re using is a generic simulator, probably PC-based albeit running custom software.

Not in the 1960s, or even the mid-80s.

True; I was thinking of current engineering development sims (e.g. the 777 and Typhoon programs you mentioned, the civil programs I worked on, etc), not the hypersonic ones mentioned here.

Since we're talking about simulators I'll add from my experience (20yrs in military flight simulators). 1960s-1970s R&D sims used a generic cockpit for a pilot with basic cockpit instrumentation with no motion system. The operator's stations were repurposed consoles from military fighter simulators reconfigured to match the cockpit instrumentation.

The computer and interface systems were special purpose machines from Link Flight Simulation, either a GP-4 or GP-4B like later model F-4s, F-111s, A-12/SR-71 and many commercial aircraft simulators used. The sim at Edwards AFB that I'm familiar with had been upgraded with a more powerful Systems Engineering Labs (SEL) Concept 32 mainframe that ran all the flight dynamics computations at 1000/second compared to a "normal" simulator that updated only 20 times/second.

My involvement was in the mid 1980s, scrounging up a shopping list of parts from the F-4 and F-111 programs to convert the existing cockpit from a B-1B to begin initial Advanced Tactical Fighter (ATF) development work.

As far as a McDonnell hypersonic flight dynamics simulator, I would have to guess it was repurpose of the Mercury spacecraft flight simulator, which was a Link Flight Simulation product that used an early version of the GP-4 system. I will also guess that such a hypersonic flight simulator would have been located in the same facility as when it was the Mercury simulator, at the McDonnell Aircraft plant at the St Louis airport.

 

[major-1]

KPM-2300 air combat stand at NIIAS (T-10 program)
Стенд воздушного боя КПМ-2300 в НИИАС (программа T-10)
1977 ??

 

[NUSNA_Moebius]

For those of you involved, when were your first experiences with 3D computer graphics as opposed to the remote control camera-over-miniature-terrain-board style? As a used to be avid gamer, I always found the close bond between the development of real-time computer graphics (aside from computers in general) and the aerospace industry fascinating.

 

[Grey Havoc]

You Can Buy This Full Motion Surplus UH-60 Black Hawk Flight Simulator From The Army

This particular model of simulator dates back to the early days of the Army's history with the venerable Black Hawk.

www.thedrive.com